i cant figure out if its my cat or the y pipe making the noise.

Does it sound like a bees in the can type noise? If it does then it your flex section. Nothing you can do about it. Either replace the whole y-pipe or live with it.

Not true, do you have the support bar under your y-pipe to hold it up?

You can always replace your flex section, but first make sure your y is not just hanging.

first figure out if its the cat or the ypipe. it could also just be a bad gasket or connection between headers and ypipe or ypipe and cat.